Occupant propelled scaffold



July 14, 1970 P. F. HALSEY ETAL 352U,38T

' OCCUPANT PROPELLED SCAFFOLD Filed Dec. 10, 1968 mvmoxs Paul F. Halsey 8| FIG.2.

United States Patent Oflice 3,520,382 Patented July 14, 1970 3,520,382 OCCUPANT PROPELLED SCAFFOLD Paul F. Halsey and Daniel C. Tevis, Wichita, Kans., assignors to Adapa, Incorporated Filed Dec. 10, 1968, Ser. No. 782,602 Int. Cl. E04g l /24 US. Cl. 182-13 2 Claims ABSTRACT OF THE DISCLOSURE A scaffold frame including an elevated platform and running gear with two transversely spaced traveling wheels. A pair of occupant actuated, independently rotatable cranks are provided on the frame adjacent the platform and drive shafts extend downwardly from the respective cranks, the drive shafts being operatively connected to the respective traveling wheels by gearing, so that the scafiold may be propelled by its occupant. Steering is effected by independent driving of the traveling wheels.

This invention relates to new and usful improvements in scaffolds such as are commonly used by painters, con-, struction workers, and the like, and which are usually provided with traveling wheels or casters so that they may be moved from one location to another as required by progress of the work. The worker using a scaffold of this type usually occupies a position on an elevated platform of the scaffold, and if the scaffold is to be moved, the worker must leave his platform and lower himself to the ground or floor in order to propel the scaffold from one location to another. Otherwise, a workers assistant must be employed to move the scaffold while the worker remains on the platform.

The principal object of the invention is to eliminate the above outlined disadvantages of conventional scaffolds so that the worker may propel the scaffold himself from one location to another without leaving his position on the elevated platform, so that considerable time and effort may be saved in performance of the work and also that employment of an assistant is not necessary in order for the scaffold to be moved.

This object is attained by the provision of an occupant propelled scaffold wherein independently rotatable hand cranks are provided on the scaffold frame adjacent the platform and are operatively connected by shafts and gearing to the traveling wheels, so that by simply rotating the cranks, the occupant may propel the scaffold from one location to another without leaving his platform. Also, steering of the scaffold is effected by driving, as afforded by independent rotation of the hand cranks.

Another important feature of the invention is that the propelling means may be easily and conveniently applied to scaffolds of conventional construction without requiring extensive modifications, as for example, in the nature of an attachment which is applicable to conventional scaffolds of various sizes and types.

With the foregoing more important object and features in view and such other objects and features which may become apparent as this specification proceeds, the invention will be understood from the following description taken in conjunction with the accompanying drawings, wherein like characters of reference are used to designate like parts, and wherein:

FIG. 1 is a perspective view of an occupant propelled scaffold in accordance with the invention;

FIG. 2 is an enlarged, fragmentary side elevational view showing one of the traveling wheels with its drive;

FIG. 3 is an end elevational view of the subject shown in FIG. 2; and

vFIG. 4 is a fragmentary view, partly in elevation and partly in section, of one of the drive shafts and actuating cranks.

Referring now to the accompanying drawings in detail, the occupant propelled scaffold in accordance with the invention is designated generally by the reference numeral 10. As far as the propelling means of the invention are concerned, the structural details of the scaffold are not important and the scaffold may be of any suitable conventional construciton which is represented in the drawings by a scaffold frame 11 which supports an elevated platform 12, occupied by a worker. Conveniently, the frame 11 may consist of two pairs of transversely spaced uprights 13, 14 by which the platform 12 is supported, the uprights in each pair being rigidly secured together by transverse rungs 15, thus forming ladders whereby access to the elevated platform may be had.

The scaffold is provided with running gear consisting of a pair of casters 16 at the lower ends of the uprights 13, and a pair of traveling wheels 17 at the lower ends of the uprights 14. Preferably, the wheels 17 may be larger in diameter than the casters 16, although not necessarily so, and if the invention is applied to a conventional, already existing scaffold, the wheels 17 may also be in the nature of casters, as for example, wherein each wheel 17 is rotatably mounted in a bearing yoke 18 having a vertical pilot pin 19 in the lower end of the associated upright 14, as is common in the art. However, for purposes of the invention the caster-type arrangement of the wheels 17 is not desirable and accordingly, the bearing yoke 18 of each wheel is provided with suitable bracket means 20 to which is connected, as by a bolt 21, a clamp ing strap 22 having a bifurcated portion 23 which straddles the lower end of the associated upright 14 and is clamped thereto as by a bolt 24. In this manner, the wheel yoke 18 is prevented from turning about the pivot pin 19 and the wheel 17 is held for rotation in a fixed plane, oriented longitudinally of the scaffold, or in other words, with the two transversely spaced wheels 17 always being coaxially disposed. Of course, if the scaffold is especially constructed for purposes of the invention, the bearing yokes 18 may be rigidly secured to the lower end of the uprights 14, thus eliminating the parts 19-24 inclusive.

In any event, the essence of the invention resides in the provision of means for propelling the scaffold from one location to another by its occupant while the latter remains on the elevated platform 12. These means comprise a pair of independently rotatable, occupant actuated hand cranks 25 which are provided on the scaffold frame adjacent the platform 12, and are operatively connected by shafts and gearing to the respective traveling wheels 17. Inasmuch as the operative connection of each crank 25 to its respective wheel 17 is the same, a description of one will suffice for both.

Each hand crank 25 is rotatably journelled in a tubular bearing 26 which may be secured directly to the scaffold frame, or if the frame structure is such that a suitable frame cross member is not available, a special cross mem ber 27 may be secured to the scaffold frame for the purpose of carrying the bearings 26 of the two cranks. Conveniently, the special cross member 27 may be telescopically extensible and contractable, so as to facilitate its installation on scaffold frames of different widths.

In any event, the lower end of each crank 25 is connected by a universal joint 28 to a drive shaft 29 which extends downwardly and has its lower end connected by a similar universal joint 30 to a stub shaft 31 which is journalled in a substantially vertical bearing tube 32 secured to one of the side plates of the aforementioned wheel bearing yoke 18, as shown in FIGS. 2 and 3. The lower end of the stub shaft 31 has secured thereto a spur gear 33 which projects through a recess 34 in the bearing yoke side plate into engagement with a crown gear 35, the latter being disposed within the yoke 18 and secured to one side of the wheel 17, as will be readily apparent. Thus, it will be understood that by rotating the hand crank 25 in one direction or the other, a drive will be imparted to the traveling wheel 17 accordingly. Moreover, since the two cranks 25 are rotatable independently, steering of the scafold by driving is facilitated.

In terms of assembly from readily available components each of the drive shafts 29 may consist of a suitable length of thin-walled tubing such as is commonly used for electrical conduits. The universal joints 28 and 30 are readily available as such and are usually provided, at least at one end thereof, with a polygonal adapter 28a (or 30a), and the joints 28, 30 may be connected to the associated drive shaft 29 by means of couplers 36 which are non-rotatably inserted into end portions of the tubular drive shaft and are provided with sockets 37 of a polygonal form to receive the polygonal adapters 28a and 30a of the universal joints, as will be understood from FIG. 4. The latter shows the drive shaft connection to the actuating crank 25, but the same arrangement may also be used in connecting the drive shaft 29 to the stub shaft 31 at the traveling wheel 17.

It will be apparent from the foregoing that the scaffold propelling means of the invention enables the occupant of the platform to move the scaffold from one location to another by simply actuating the hand cranks 25 and without the conventionally experienced necessity of leaving the platform in order to move the scaffold by hand from the ground or floor, thus saving considerable time and effort and also avoiding the conventional necessity of,

employing an assistant to move the scaffold while the worker remains in position thereon.

What is claimed as new is:

1. An occupant propelled scaffold with steering by driving means, comprising in combination a scafiold frame including an elevated occupant supporting platform, running gear for said frame including a pair of transversely spaced and independently rotatable traveling wheels, a pair of 0ccupant actuated independently rotatable cranks provided on said frame adjacent said platform, a pair of drive shafts connected to the respective cranks and extending downwardly therefrom toward said wheels, and gearing operatively connecting said drive shafts to the respective wheels, said frame also including a pair of transversely spaced uprights, together with a pair of bearing yokes provided at the lower ends of the respective uprights, said travel ing wheels being rotatably mounted in the respective yokes each of said yokes including a side plate provided with a recess, a substantially vertical bearing tube provided on said side plate with one end thereof disposed adja cent said recess, and a stub shaft rotatably journalled in said bearing tube, said stub shaft having an upper end operatively connected to one of said drive shafts and said gearing comprising a crown gear rotatable with and disposed at one side of the associated traveling wheel in said yoke, and a spur'gear secured to the lower end of said stub shaft, said spur gear projecting through said recess in the yoke side plate into engagement with said crown gear.

2. The device as defined in claim 1 together with a universal joint operatively connecting said stub shaft to the lower end of the associated drive shaft.

References Cited UNITED STATES PATENTS 2,183,679 12/1939 Hillis 182-16 2,989,139 6/1961 Pantek 18216 -1,354,370 9/1920 Anechiarico 182-13 FOREIGN PATENTS 208,929 4/1909 Germany.

REINALDO P. MACHADO, Primary Examiner U.S. Cl. X.R. 18216 

